Display panels of the type described above, known as PANAPLEX panels, have been available commercially for some time. In general, these panels are manufactured by forming the various electrodes on the base plate and face plate of the panel envelope, sealing together the base plate and face plate, baking out the envelope through a tubulation secured to the base plate, filling the envelope with the desired gas through the tubulation, etc. These processing steps are essentially all separate operations and require the panel to be handled many times and processed in different types of ovens and other apparatus.
In order to reduce costs of manufacture, it would be desirable to eliminate the tubulation and perform the majority of the processing operations in one location and with minimal apparatus. Various suggestions have been made for achieving these goals; however, none has been completely satisfactory.